Hydraulic regulating device



Dec. l, 1970 A, wALz 3,544,237

` HYDRAULIC REGULATING DEVICE I Filed Dec. 19. 1968 ALFRED WALZ ATTORNEYUnted States Patent Olce 3,544,237 Patented Dec. 1, 1970 3,544,237HYDRAULIC REGULATING DEVICE Alfred Walz, Emmendingen, Germany, assignorto Dornier System G.m.b.H., Friedrichshagen, Germany, alimited-liability corporation of Germany Filed Dec. 19, 1968, Ser. No.785,193 Int. Cl. F04f 11/00; F163 3/00; F16h 21 44 U.S. Cl. 417-48 10Claims ABSTRACT F THE DISCLOSURE A porous diaphragm is provided withelectrode means on opposite sides thereof. Means is provided forapplying electrical potential of varying polarity to the electrodemeans. A reservoir means is disposed at either side of the diaphragm anda uid lls the space within the reservoir means and the spaces deiinedadjacent the diaphragm. A body means supports the diaphragm and includesgrooves for distributing the uid. An output means is connected with thereservoir means for operating a suitable mechanism.

BACKGROUND OF THE INVENTION The present invention relates to a pumputilizing electrokinetic elects and includes an output means which isoperated by the pump and may be connected with a suitable mechanism tobe operated.

The apparatus of the present invention may be employed for example forcontrolling the position of the rudder in a ship or airplane. Suchrudders are remotely controlled and commonly employ mechanisms which arecontrolled from a remote station by means of a hydraulic system. Suchhydraulic systems are disadvantageous since the hydraulic lines areunder relatively high pressure and may be of considerable length. Thesefactors coupled with the vibration encountered in ships and airplanescause serious problems in obtaining proper sealing of the hydraulicsystem.

Known types of pumps employ an electrically conductive fluid which iscaused to move due to an induction effect by the application of amagnetic eld. This type of pump is expensive in construction and is veryheavy because of the magnetic parts required such as pole pieces, etc.,as well as the necessary electrical windings and source of electricalcurrent. Such pumps have been used as electrohydraulic control devices.

It is accordingly desirable to provide an improved pump which can beemployed as a control means in the immediate area of a mechanism to beoperated, and further wherein the pump can be connected to a remotecontrol station by way of control lines that are as small as possibleand Which will eliminate sealing problems. It is further advantageous toprovide a compact self-contained pump unit including an output meanswhich can be connected to an adjacent mechanism to be operated.

SUMMARY OF THE INVENTION In the present invention, a porous diaphragm issupported within a body means and has electrode means disposed onopposite sides thereof. A exible reservoir means is disposed at eachside of the diaphragm, and a fluid is disposed within the reservoirmeans and in contact with the diaphragm means and in the spaces definedadjacent the diaphragm means. Electrical leads are connected with theelectrode means and extended to a remote control station so that anelectric potential of suitable polarity may be selectively applied tothe electrode means at either side of the diaphragm. Upon theapplication of a suitable electric potential to the electrode means,electroosmosis occurs and the uid will permeate the porous diaphragm ina predetermined direction.

The flow of uid from one side of the diaphragm to the other will causemovement of the llexible reservoir means which is interconnected with asuitable output means, in turn connected with any suitable mechanism tobe operated.

Pressures on the order of up to approximately 50 atmospheres and abovecan be produced with the arrangement of the present invention, and thesepressures are created directly at the location Where pressure isrequired. The electrical leads connecting the apparatus with a remotecontrol station occupy only a minimum of space and provide aconsiderable advantage over conventional hydraulic lines.

The structure of the present invention is quite small and compact, andprovides a self-contained unit which is particularly suitable to beemployed as a control device in airplanes.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal cross-sectionof a rst embodiment of the present invention;

FIG. 2 is a sectional view taken substantially along line 2-2 of FIG. 1looking in the direction of the arrows; and

FIG. 3 is a longitudinal cross-section through a modied form of theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawingswherein like reference characters designate corresponding partsthroughout the several views, a rst form of the invention is illustratedin FIGS. 1 and 2 of the drawings. A body means includes a pair of flatcircular plates 10 and 12 which are clamped between a pair of generallycup-shaped cover members 14 and 16, all of members 10, 12, 14 and 16being held in operative position as illustrated by suitable nut and boltassemblies 18.

A porous disc-like diaphragm 30 is clamped within suitable recessesprovided in plates 10 and 12 and is retained thereby in the operativeposition illustrated. Electrode means 32 and 34 are clamped betweenplates 10 and 12 and on opposite sides of the diaphragm and are suitablyinsulated from one another by conventional insulating means (not shown).Electrical leads 36 and 38 extending through suitable holes provided inplates 10 and 12 are connected with the electrode means 32 and 34respectively. Diaphragm 30 is formed of a porous electrical insulatingmaterial having capillaries and pores formed therethrough. The poreshave a radius which is no greater than about 10'i millimeters. Asubstance which is particularly suitable for use as a diaphragm materialis pure quartz produced by sintering quartz or by etching out the glassconstituents from a pure quartz-glass melt. The electrode means arepreferably in the form of networks and may for example comprise metalwires or carbon lilaments.

The electrode means is illustrated as being directly in Contact with thediaphragm, but it is also possible and even desirable to mount theelectrode means in spaced relationship to the adjacent surfaces ofdiaphragm. The advantage of spacing the electrode means from thediaphragm. The advantage of spacing the electrode means from thediaphragm is that the fluid means of the apparatus can readily reach allof the capillaries and pores of the associated diaphragm.

A pair of separate and independent reservoir means 40 and `42 areprovided at opposite sides of the diaphragm. Each of these reservoirmeans is of a exible construction and may comprise a bellows arrangementas illustratedwhe're'bythe two reservoir means can expand and contractin an axial direction along the longitudinal axes thereof. Reservoirmeans 40 and 42 include neck portions 44 and 46 which are receivedwithin central holes formed in the plates and 12 respectively, theseneck portions being iiared outwardly at the inner ends thereof so as toretain the neck portions of the reservoir means in placewith respect tothe associated plates.

The faces of plates 10 and 12 adjacent to the diaphragm are providedwith a plurality of annular grooves 50 and 52 respectively, grooves 50having annular tapered ridges 50' disposed therebetween, and grooves 52having annular tapered ridges 52 formed therebetween. Ridges 50 haveline lcontact with electrode means 32, and ridges 52 have line contactwith electrode means 34. This arrangement minimizes the area of contactbetween the plates and the electrodes, and the effective surface of thediaphragm remains large. A plurality of substantially radially extendinggrooves 54 are provided in plate 10 to provide a communication betweenadjacent grooves 50 so that the fluid means can readily circulatebetween the diiferent grooves and over the surface of the diaphragm.Similar radial grooves 56 are provided in plate 12 to providecommunication between adjacent grooves 52. In an arrangement wherein theelectrodes are spaced from the diaphragm, the radial grooves may beomitted.

A fluid means is provided and may comprise a suitable liquid such ashighly pure distilled water which has been degassed to free it fromcarbonio acid and which has a specific resistance of at least 106 ohmscm., and preferably at least 107 ohms cm. The body of liquid isindicated by reference numeral 60 and iills the space defined within thetwo reservoir -means 40 and 42 and also iills the spaces defined betweenopposite sides of the diaphragm and the adjacent portions of the plates10 and 12. It is apparent that the radial and annular grooves providedin the faces of plates 10 and 12 will serve to distribute the liquidover the face of the diaphragm while at the same time enabling thediaphragm to be held in place by the plates 10 and 12.

All of the portions of theapparatus which are in contact with the iiuidmeans must be chemically inert thereto. A platinum coating over themetallic parts has been found to provide good results. Rhodium,palladium and gold may be also employed for coating those portions ofthe apparatus in contact with the liquid. Among organic substances,polytetrauoroethylene (Teon) is suitable.

Reservoir means 40 and 42 are connected respectively with members 64 and66 aligned with the longitudinal axes thereof and slidably extendingthrough suita'bleholes provided in the outer ends of cover members 14and 16.

Members 64 and 66 carry pins 68 and `70 which are slidably positionedwithin slots 72 and 74 of levers 76 and 78 respectively. Levers 76 and78 are pivotally supported by pins 80 and 82, and the outer ends ofthese levers are connected by pins 84 and 86 with spacedportions of anoutput member 90. 1t will be noted that the two levers 76 and 78 alongwith output member 20 define a parallelogram linkage. Output member 90may be connected with any suitable mechanism which it is desired tooperate.

When a suitable potential is applied to the electrode means on diaphragm30, the fluid medium permeates the diaphragm in a particular directiondepending on the polarity vapplied to the electrode means. As shown, apotential of suitable polarity has been applied to the diaphragm meansto cause the iiuid to flow from reservoir liow is `provided due to theprovision of the grooves in means 42 through the diaphragm means tocause the uid `to flow from reservoir means 42 through the diaphragminto reservoir means 40 whereby the pressure in reservoii means l42deceases while the pressure in reservoir means 40 increases. Reservoirmeans 40 accordingly expands to the left as seen inthe drawings to movemember 64 later- `ally outwardly of the body means. The diaphragm meansis retained in the clamped operative position by the plates 10 and 12and relatively uniform distribution of the fluid the two plates 10 and12.

Outward movement of member 64 as aforedescribed will cause lever 76 topivot so that the output member 90 moves in the direction of the arrowas seen in` FIG. 1 whereby the mechanism connected with output member isoperated.

As member moves from left to right as seen in FIG. 1, lever 78 will bepivoted so as to move member 66 inwardly or from right to left therebyreducing the volume of reservoir means 42. Accordingly, the volume ofreservoir means 42 is decreased as the volume of reservoir means 40increases so that no negative pressure is created and no evaporation ofthe fluid means will occur. It is apparent that in order to move theoutput member in the opposite direction, the electrical polarity appliedto the electrode means is simply reversed.`

Referring now to FIG. 3 of the drawings, a modiiied form of theinvention is illustrated. This arrangement is similar in many respectsto that shown in FIG. 1, and similar components have been given the samereference numerals primed. It will be noted that only a single outputlever 78 corresponding to the output lever 78 of the previouslydescribed structure is provided, lever 78' being in turn directlyconnected with a suitable output member or mechanism to be operated.

Instead of providing the reservoir means 40 to the left of the diaphragmas in the previous embodiment, a reservoir means in the form of anelastic container is provided including a neck portion 102 which is aredinwardly so as to secure it in a central hole provided in plate 10. Thiselastic container as well as` reservoir means 42' and the spaces definedbetween the diaphragm and adjacent parts 10' and 12' are all tilled witha suitable fluid means as in the previously described arrangement.

When it is desired to operate lever 78', an electrical potential isapplied to the electrodes carried by the diaphragm so that the -uidmeans will permeate the diaphragm from the elastic container 100 intoreservoir means 42f causing the reservoir means to expand in an axialdirection thereby swinging lever 78' in the direction indicated by thearrow.

When the electrical polarity is reversed so that the uid medium flowsfrom reservoir means `42' into elastic container 100, Vthere is atendency to develop a negative pressure of fractions of an atmospherewhich will cause a fluid means such as water to evaporate. Accordingly,strong return springs may be provided to ensure that reservoir Vmeans42' will be reduced in volume concurrently with ow of fluid therefromthrough the diaphragm.

It Will be obvious to those skilled in the art that many modificationsmay be made within the scope of the present invention Without departingfrom the spirit thereof, and the invention includes all suchmodiiications.

What is claimed is:

1.A hydraulic regulating device comprising a porous diaphragm, supportmeans for holding said diaphragm in position, said support meanscomprising relatively rigid body means and including groove means formedin said `body means adjacent said diaphragm for distributing fluid alongthe surfaces of the diaphragm, said groove means in said body meansincluding annular groove means and radial groove means in communicationwith said annular groove means, electrode means disposed on oppositesides of said diaphragm, means for applying an electrical potential tosaid electrode means, reservoir means at opposite sides of saiddiaphragm, and fluid means in said reservoir means and in contact withsaid diaphragm, said iiuid means permeating said diaphragm uponapplication of a suitable electrical potential to said electrode means.

2. Apparatus as defined in claim I1 wherein said electrode means ismounted adjacent opposite faces of said diaphragm.

3. Apparatus as dened in claim 4 wherein said electrode means comprisenetwork electrodes.

4. Apparatus as defined in claim 1 wherein said reservoir means is offlexible construction and is adapted to expand and contract.

S. Apparatus as defined in claim 4 wherein said reservoir meanscomprises a bellows construction whereby the reservoir means can expandand contracting along a longitudinal axis thereof.

6. Apparatus as defined in claim 1 including output means operativelyconnected with said reservoir means.

7. Apparatus as defined in claim 1 wherein said reservoir means includesa separate and independent movable reservoir at each side of saiddiaphragm, and output means including a pair of movable members each ofwhich is connected with one of said reservoirs.

8. Apparatus as defined in claim 7 including an output memberinterconnected with said pair of movable members to form a parallelogramarrangement.

9. Apparatus as defined in claim 1 including output means comprising anoutput member interconnected only with the reservoir means at one sideof said diaphragm. 10. Apparatus as defined in claim 1 wherein theinterior of said reservoir means in contact with said fluid means iscovered with a layer of material which is chemically inert to said uidmeans.

References Cited WILLIAM L. FREEH, Primary Examiner U.S. Cl. X.R. 92-37;74-104

